He first floated the idea on Nick Ferrari's LBC show last week. The Sunday Times followed his lead, reporting that a new "living bridge" across the Thames was planned and quoting the Mayor's claim "that [it] will once again provide a commercial zone...a bridge that actually has residential and commercial property on it, as the old London Bridge did". It continued:

Early plans being drawn up by Anthony Brown (sic), Johnson's policy director, are being modelled on designs by Antoine Grumbach, the French architect who won a competition to design a habitable bridge held by the Royal Academy in 1996.

It's the same sales pitch as Boris's Bus: a new product that claims to revive a historic, nay, "iconic" feature of the capital. The notion hasn't impressed the Guardian's Jonathan Glancy:

Surely Johnson cannot really be keen on such a dubious structure, set between Waterloo and Blackfriars Bridge, and based on designs by the French architect Antoine Grumbach shown at the Royal Academy's fine exhibition of Living Bridges 13 years ago? This takes the form of massively high towers given over to "luxury" flats, shops and restaurants, and a kind of miniature Kew Gardens spanning the Thames itself.

"Massively high towers"? I thought we were against those. Judge the 1996 Grumbach design for yourself here (pdf) then absorb more of Jonathan's verdict:

I can see how the Johnson-Grumbach project adds up. An opportunity to build more costly, showy flats in central London and to serve up ever more lucrative chain shops and over-branded cafes to supposedly gormless Londoners still apparently hungry for more bland, packaged food and shiny knick-knacks.

I wonder if this is yet another side-effect of the recession: proposing scarcely believable super-projects is a great way of getting press, without the inconvenience of actually having to build the things. Rafael Vinoly's 300m eco-tower at Battersea Power Station was exactly the same thing, no matter what Treasury Holdings might tell you.

And what's more:

Boris Bridge is clearly nothing more than a gigantic McGuffin...I promised to eat my own hat if Boris Airport ever got built. If Boris Bridge gets built, I will eat yours. All of yours. You can send me an enormous box of hats and I will live off it for a year.